Stockfish

* fixed `get_stockfish_major_version` method when version of stockfish is floating-point number (Thank you, Pavocracy)

* added method `make_moves_from_current_position` that allows the position to be updated by making moves from the current position
* small internal improvement

Thank you johndoknjas :)

* added the `get_top_moves function`, which gives info on Stockfish's top PVs
* `self._parameters` is assigned to a deep copy of self.default_stockfish_params, which prevents the latter from being modified when self._parameters.update(parameters) happens

Thank you johndoknjas

* Fixed unique parameter issue for multiple objects 53 (thank you VivekThazhathattil)

* Added elo rating support

Thank you mickkn

* added stockfish `quit` command to class destructor